Method for cladding metal



United States Patent [72] Inventor Charles F. Funk Metalrie, Louisiana [21 1 Appl. No. 668,486 [22] Filed Sept. 18, 1967 [45] Patented Dec. 8, 1970 [73] Assignee Shapeweld,lnc.

New Orleans, Louisiana a corporation of Louisiana. by mesne assignments [54] METHOD FOR CLADDING METAL 1 Claim, 3 Drawing Figs.

[52] US. Cl .4 164/98,

164/337 [51 Int. Cl. B22d 19/00 50] Field of Search 164/54. 65. 86. 88. 92. 98. 106.129. 133,332, 333.334. 335. 337. 548: 249/90. I05. I08. (Cursory) [56] References Cited UNITED STATES PATENTS 42,894 5/1864 Williams 164/333X 673,548 5/1901 Proeger l64/254X 1,314,874 9/1919 Knadler.... l64/333X 2,309,288 1/1943 Young 164/54 2,931,082 4/1960 Brennan l64/88X 3,396,778 8/1968 Jensen et al. 164/138X 2,028,699 1/1936 Greene et a1. 249/108 1,738,056 12/1929 Hunter 249/90X 2,310,915 2/1943 Hurley 164/332X 2,763,044 9/1956 Brennan 164/86X 3,200,452 8/1965 Williamson l64/133X Primary Examiner-.1. Spencer Overhollser Assistant Examiner-V. K. Rising Attorney-Hyer. Eickenroht, Thompson & Turner ABSTRACT: In the metal-cladding method disclosed a body of molten metal is located above the surface of the base metal to be clad. The metal is allowed to flow downwardly toward the surface through a restriction that shapes the metal striking the surface into an elongated narrow stream. The stream is about as long as the longest dimension of the surface being clad. The apparatus of the invention includes a mold having a crucible to hold the molten metal and a slot for restricting the flow of the molten metal into the mold cavity enclosing the surface being clad. The slot shapes the metal into an elongated, narrow stream that is about as long as the longest dimension of the surface being clad.

1 the surface being clad.

I METHOD FOR CLADDING METAL This invention relatesto a method of and apparatus for cladding the surface of a" metal body with a layer of metal.

There are many instanceswhere it would be desirable to add to or-rebuild the surface of a. body of metal. For example, wear plates and hammers wear'away in use and have to be metal over the surface of 'a body of base metal. The molten metal issupposed to supply the heat to fusethe added metal to the surface being clad as it solidifies. Thismethod has been unsatisfactory in the past because complete fusion was seldom, if ever, obtained between t he added or clad metal and the base metal. Furthen the depthof fusion often varied considerably.' n the areas where little or no fusion existed, the clad metal layer would chip off 'in service, causing additional down time and expense, with the-result that no savings are realized in the attempt to reuse the worn, rebuilt member.

It is an object of this invention to provide apparatus for and a method of cladding the-surface of a metal body that consistently produces complete fusion between the clad metal and It is another object of this invention to provide apparatus for and a method of cladding the surface of a metal body that produces substantially uniform'fusion-of the clad metal to the base metal along the entirelength of the surface being clad.

These and other objects, advantages, and features of the invention willbeapparent to those skilled in theart; from a con lside'ra'tion of; this} specification, attached drawings, and appended claims." r t The preferred embodiment of the apparatus for practicing the method of this invention will now be described in connection with the attached drawings in which,

FIG. 1 isa cross sectionalviewof the apparatus set up to clad the surface of a worn hammer from ahammer mill;

FIG. 2'is a view on an enlargedscale taken along line 2-2of FlG.l;andh

' FIG. 3 is a view along line 3-3 of FIG. 1. V

y In H6. 1 the apparatus is set upto rebuild worn hammer 10, a typical hammer from a hammer mill. The end-of the hammer has been worn awaysufficientlyto require the hammer to be removed from the mill. Therportion of thchammer remaining is undamaged. Therefore, if the metal that has been worn off could be replaced, the hammer-{could be used again.

Preferably, before the cladding operation is begun, the worn 12 to which the clad metal may be fused. This is not necessary.

' It is desirable, however, since it allows the exact volume of Supporting the weight of thehammer is channel 20, arranged as shown in FlG. 3. A channel is used to allow the lower edges screw assembly.

.ofthe hammer to be fully supported even if it is necessary to Dividing the mold box into an upper and lower section is horizontal partition 22. Thepartition isprovided with opening 22a, through which thehammer extends. The upper end of hammer 10 is enclosed by r'nold24zThemold comprises two halves 24a and 24b, which are identically shaped so'thatwhen brought together they will appear; as shown in FIG; 1, with parting line 25 intersecting the center line of surface 12. The

moldhalves are supported on fire lbrick' 26 and molding sand.

27 is placed around the bottomof the mold tohold it in position and also to keepmolden metal fromescaping from the mold. i I

Upper portion 28 of mold 24 provides a crucible to hold a given amount of prereacted thermit materialiln the embodiment shown, crucible'section28 includes bowl-shaped portion 29 formed 'by'the two: mold halves and tubular member 30, which i's'supported on annular shoulder 3i adjacent the top of the mold. Tubular member 30 in the embodiment shown is a section of thick-walled steel pipe. r i

It is intended that the mixture 'of thermit placed in the crucible and reacted in place. It will then be allowed to flow downwardly into metal-shaping section 33 of the mold. The metal shaping section of the mold'forms cavity 34 into which the upper end of hammer 10 extends. This cavity is shaped to restore hammer'jlll to its original dimensions.

Therefore, the distancefrom the end of the hammer to the Qonnecting cavity 34 of the'melal-shaping section and the crucible section is passageway 36. Thepassageway comprises I end of the hammer is cut off to present square smooth surface metal req'uiredto restore the hammer to its original dimensions to be more accurately calculated. Also, by cutting off the I end of the hammer, so that it will be substantially flat and level when placed in the mold, the molten metal to be directed against the surface will flow over the surface uniformly. Hammer 10 is placedin mold box-l4, which holds the hammer in avertical positionwith surface 12 level. To hold the hammer in this position, plate 16 is fixed to the bottom of the mold box withflat side 16:; vertical. Lock screw assembly 18 holds the hammer againstside 16a of plate 16. The lock screw assembly includes threaded rod 18a, which extends through threaded nut 18b, attached to the side of the'mold an elongatednarrow slot that extends substantially the length of the surface to be clad. in theembodiment shown,;this would be surface 12 shown dotted in FIG. 2. The purpose of slot 36 is j to restrict the flow of the liquid metal from the crucible section sufficiently for the metal'toflow evenly through slot 36 against surface 12 of the hammer in-along narrow stream of uniform thickness. Therefore, thewidth of the-slot must be designed to provide this-restriction. For example, when rebuilding a hammerS-l/a inches thick and. 9 inches wide" by adding 2 k inches of metal to the end of thehammer, a slot substantially as long as the longest dimension of the surface being clad, i.e., 9 inches, and between one-quarter and threewhen building up the hammers 2% inches. These latter. hammers are approximately 9 inches long when finished.

In the preferred embodiment, thelower end of the crucible is provided with opening '38. Inwardly extending annular flange 39, located in the opening provides upwardly facing an- 1 nular. shoulder 39a. 'Metal. disc (not shown) are placed on box.The rod has head I8c locatcd on the outside of the box 7 and provided with wrench flats so that the rod can be rotated by a wrench. Rotating the rod moves it axially into and out of the mold box. The opposite end vof the rod from head 180 is with hammer 10 to hold it against plate 16 by rotating rod 18a.

shoulder 39'to hold the thermit' material in'the cruciblesection long enough for it to react completely and for the slag to rise to the top. The plates thenmelt and allow the metal to flow downwardly into the metal forming section. Below opening 38 to lead the metal to slot36 the mold is provided with opposed downwardly coverging curved surfaces 40a and 40b.

To practice the method of this invention, the quantity of therrnit material required to provide the necessary volume of metalis placed in the crucible. above the surface to be clad. 1

The material is reactedandheld in the crucible long enough for the slag to rise to the top. It then flows downwardly material will be metal toward the surface is restricted sufiiciently by slot 36 to form the liquid metal into an elongated narrow stream that is as long as the slot and substantially as long as the surface being clad. The 'nietal is confined to the surface and formedinto the desired configuration by the mold cavity above the surface.

: It is believed that the'subst'antially uniform fusion obtained betw'eenthe base metal and the clad metal by the method and apparatus of thisinvention results in part from the shape of the elongated narrow stream of metal that is directed downwardly against the surface being clad with considerable force. The

shape of the'j 'sti'eam produces uniform turbulence in the body of molten rnetal: above or adjacent the surface being clad and :causes the e ntires'urface to be raised to fusion temperature before any'of the molten metal begins to solidify. Further, by

forming the metal'into a'stream substantially as long as the longest dimensionj of the surface being clad, the distance the metal flows across the surface to reach the mold is a minimum. This reducesthe amount of heat given up by the molten metal well adapted to attain all of the ends and objects hereinabove set forth, togetherwith other advantages which are obvious and which are inherent to the method and apparatus.

It will be understood that certain features and subcombinations are of utility and may be employedwithout reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter hereinset forth or shown in the accompanying drawings is to.be interpreted as illustrative-and not in a limiting sense.

I claim:

l. A method of cladding the surface of a body of metal cornprising directing a stream of molten metal downwardly toward the surface being clad through a passageway, restricting the downward flow of molten metal in the passageway, and forming the molten metal into an elongated narrow stream substantiallyas long as the surface before the metal leaves th passageway and falls freely toward the surface. 

